Re: [Matplotlib-users] Updated Lasso Demo
+1 for including Brian's changes in the shipping example.
Brian, You might also be interested in an alternate, polygon-based
lasso I developed a while back. Though it meets my needs, beware of
backend-specific problems with idle events that I never resolved.
-Eric
http://www.nabble.com/Alternate-lasso:-click-to-form-polygon-td18724261.html
On Sun, Dec 7, 2008 at 10:24 AM, B Clowers wrote:
> When running the initial lasso demo I found that only one lasso event was
> allowed and other canvas interaction events (e.g. zooming) would not work
> properly after the lasso event. As such I came up with my own solution to
> the problem by modifying the example source. The primary addition was a
> button release event call and a boolean to keep track whether the lasso was
> the last event to lock the widget from interaction. Anyway, I hope it can
> help someone else out.
>
> Cheers,
>
> Brian
>
>
> """
> Show how to use a lasso to select a set of points and get the indices
> of the selected points. A callback is used to change the color of the
> selected points
>
> This is currently a proof-of-concept implementation (though it is
> usable as is). There will be some refinement of the API and the
> inside polygon detection routine.
> """
> from matplotlib.widgets import Lasso
> import matplotlib.mlab
> from matplotlib.nxutils import points_inside_poly
> from matplotlib.colors import colorConverter
> from matplotlib.collections import RegularPolyCollection
>
> from matplotlib.pyplot import figure, show
> from numpy import nonzero
> from numpy.random import rand
>
> class Datum:
> colorin = colorConverter.to_rgba('red')
> colorout = colorConverter.to_rgba('green')
> def __init__(self, x, y, include=False):
> self.x = x
> self.y = y
> if include: self.color = self.colorin
> else: self.color = self.colorout
>
>
> class LassoManager:
> def __init__(self, ax, data):
> self.axes = ax
> self.canvas = ax.figure.canvas
> self.data = data
> #the lasso lock boolean is used to tell whether another
> #widget event has priority
> self.lassoLock = False
>
> self.Nxy = len(data)
>
> facecolors = [d.color for d in data]
> self.xys = [(d.x, d.y) for d in data]
> fig = ax.figure
> self.collection = RegularPolyCollection(
> fig.dpi, 6, sizes=(100,),
> facecolors=facecolors,
> offsets = self.xys,
> transOffset = ax.transData)
>
> ax.add_collection(self.collection)
>
> self.cid = self.canvas.mpl_connect('button_press_event',
> self.onpress)
> self.cidRelease = self.canvas.mpl_connect('button_release_event',
> self.onrelease)
>
> self.ind = None
>
> def callback(self, verts):
> facecolors = self.collection.get_facecolors()
> ind = nonzero(points_inside_poly(self.xys, verts))[0]
> for i in range(self.Nxy):
> if i in ind:
> facecolors[i] = Datum.colorin
> else:
> facecolors[i] = Datum.colorout
>
> self.canvas.draw_idle()
> self.canvas.widgetlock.release(self.lasso)
> #del self.lasso
> self.ind = ind
>
> def onpress(self, event):
> if self.canvas.widgetlock.locked(): return
> if event.inaxes is None: return
> self.lasso = Lasso(event.inaxes, (event.xdata, event.ydata),
> self.callback)
> # acquire a lock on the widget drawing
> self.canvas.widgetlock(self.lasso)
> # establish boolean that can be used to release the widgetlock
> self.lassoLock = True
>
> def onrelease(self, event):
> 'on release we reset the press data'
> # test whether the widgetlock was initiated by the lasso
> if self.lassoLock:
> self.canvas.widgetlock.release(self.lasso)
> self.lassoLock = False
> print self.ind
>
>
> if __name__ == '__main__':
>
> data = [Datum(*xy) for xy in rand(100, 2)]
>
> fig = figure()
> ax = fig.add_subplot(111, xlim=(0,1), ylim=(0,1), autoscale_on=False)
> lman = LassoManager(ax, data)
>
> show()
>
>
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The future of the web can't ha
[Matplotlib-users] Updated Lasso Demo
When running the initial lasso demo I found that only one lasso event was
allowed and other canvas interaction events (e.g. zooming) would not work
properly after the lasso event. As such I came up with my own solution to the
problem by modifying the example source. The primary addition was a button
release event call and a boolean to keep track whether the lasso was the last
event to lock the widget from interaction. Anyway, I hope it can help someone
else out.
Cheers,
Brian
"""
Show how to use a lasso to select a set of points and get the indices
of the selected points. A callback is used to change the color of the
selected points
This is currently a proof-of-concept implementation (though it is
usable as is). There will be some refinement of the API and the
inside polygon detection routine.
"""
from matplotlib.widgets import Lasso
import matplotlib.mlab
from matplotlib.nxutils import points_inside_poly
from matplotlib.colors import colorConverter
from matplotlib.collections import RegularPolyCollection
from matplotlib.pyplot import figure, show
from numpy import nonzero
from numpy.random import rand
class Datum:
colorin = colorConverter.to_rgba('red')
colorout = colorConverter.to_rgba('green')
def __init__(self, x, y, include=False):
self.x = x
self.y = y
if include: self.color = self.colorin
else: self.color = self.colorout
class LassoManager:
def __init__(self, ax, data):
self.axes = ax
self.canvas = ax.figure.canvas
self.data = data
#the lasso lock boolean is used to tell whether another
#widget event has priority
self.lassoLock = False
self.Nxy = len(data)
facecolors = [d.color for d in data]
self.xys = [(d.x, d.y) for d in data]
fig = ax.figure
self.collection = RegularPolyCollection(
fig.dpi, 6, sizes=(100,),
facecolors=facecolors,
offsets = self.xys,
transOffset = ax.transData)
ax.add_collection(self.collection)
self.cid = self.canvas.mpl_connect('button_press_event', self.onpress)
self.cidRelease = self.canvas.mpl_connect('button_release_event',
self.onrelease)
self.ind = None
def callback(self, verts):
facecolors = self.collection.get_facecolors()
ind = nonzero(points_inside_poly(self.xys, verts))[0]
for i in range(self.Nxy):
if i in ind:
facecolors[i] = Datum.colorin
else:
facecolors[i] = Datum.colorout
self.canvas.draw_idle()
self.canvas.widgetlock.release(self.lasso)
#del self.lasso
self.ind = ind
def onpress(self, event):
if self.canvas.widgetlock.locked(): return
if event.inaxes is None: return
self.lasso = Lasso(event.inaxes, (event.xdata, event.ydata),
self.callback)
# acquire a lock on the widget drawing
self.canvas.widgetlock(self.lasso)
# establish boolean that can be used to release the widgetlock
self.lassoLock = True
def onrelease(self, event):
'on release we reset the press data'
# test whether the widgetlock was initiated by the lasso
if self.lassoLock:
self.canvas.widgetlock.release(self.lasso)
self.lassoLock = False
print self.ind
if __name__ == '__main__':
data = [Datum(*xy) for xy in rand(100, 2)]
fig = figure()
ax = fig.add_subplot(111, xlim=(0,1), ylim=(0,1), autoscale_on=False)
lman = LassoManager(ax, data)
show()
"""
Show how to use a lasso to select a set of points and get the indices
of the selected points. A callback is used to change the color of the
selected points
This is currently a proof-of-concept implementation (though it is
usable as is). There will be some refinement of the API and the
inside polygon detection routine.
"""
from matplotlib.widgets import Lasso
import matplotlib.mlab
from matplotlib.nxutils import points_inside_poly
from matplotlib.colors import colorConverter
from matplotlib.collections import RegularPolyCollection
from matplotlib.pyplot import figure, show
from numpy import nonzero
from numpy.random import rand
class Datum:
colorin = colorConverter.to_rgba('red')
colorout = colorConverter.to_rgba('green')
def __init__(self, x, y, include=False):
self.x = x
self.y = y
if include: self.color = self.colorin
else: self.color = self.colorout
class LassoManager:
def __init__(self, ax, data):
self.axes = ax
self.canvas = ax.figure.canvas
self.data = data
#the lasso lock boolean is used to tell whether another
#widget event has priority
self.lassoLock = False
self.Nxy = len(data)
facecolors = [d.color for d in data]
self.xys = [(d.x, d.y) for d in data]
fig = ax.figure
